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Texas CDL Combination Vehicles: test 3

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Combination Vehicles 3

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Question 1 of 5
  1. 1. You are unsure whether the parked trailer has spring brakes. What should you do before uncoupling?
  2. 2. When uncoupling a loaded trailer, how far should you lower the landing gear after firm ground contact?
  3. 3. How should the disconnected trailer electrical cable be stored?
  4. 4. While operating the fifth-wheel release, where should your legs and feet be?
  5. 5. You have pulled the fifth-wheel clear but kept the tractor frame under the trailer. What should you verify before pulling away fully?
Review all 5 questions with answers

  1. You are unsure whether the parked trailer has spring brakes. What should you do before uncoupling?

    Correct answer: Chock its wheels

    Stored air can leak away; use chocks when spring-brake protection is uncertain.

    Source: Texas DL-7C, March 2026, section 6, PDF page 99: Coupling and uncoupling ↗

  2. When uncoupling a loaded trailer, how far should you lower the landing gear after firm ground contact?

    Correct answer: A few extra turns in low gear to unload some tractor weight, without lifting off the fifth-wheel

    Support some weight to ease release without creating an unsafe gap or over-lifting.

    Source: Texas DL-7C, March 2026, section 6, PDF page 99: Coupling and uncoupling ↗

  3. How should the disconnected trailer electrical cable be stored?

    Correct answer: Supported with the plug pointing down to keep moisture out

    Protect the plug from moisture and the cable from moving parts or road damage.

    Source: Texas DL-7C, March 2026, section 6, PDF page 99: Coupling and uncoupling ↗

  4. While operating the fifth-wheel release, where should your legs and feet be?

    Correct answer: Clear of the tractor’s rear wheels

    Unexpected vehicle movement can cause severe injury near the wheels.

    Source: Texas DL-7C, March 2026, section 6, PDF page 99: Coupling and uncoupling ↗

  5. You have pulled the fifth-wheel clear but kept the tractor frame under the trailer. What should you verify before pulling away fully?

    Correct answer: The landing gear is sound and the ground supports the trailer

    Check support while the tractor is still positioned to limit a trailer fall.

    Source: Texas DL-7C, March 2026, section 6, PDF page 100: Coupling and uncoupling ↗

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Question reference: tx-cdl-combo-041

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States / Texas / CDL

Texas CDL Combination Vehicles: test 3

5 questions from this subject. 45 questions on trailer control, air connections, coupling and uncoupling.

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